On the Behavior of the iPhone Mute Switch

Friday, 13 January 2012

The unmistakably jarring sound of an iPhone marimba ring
interrupted the soft and spiritual final measures of Mahler’s
Symphony No. 9 at the New York Philharmonic on Tuesday night. The
conductor, Alan Gilbert, did something almost unheard-of in a
concert hall: He stopped the performance. But the ringing kept on
going, prompting increasingly angry shouts in the audience
directed at the malefactor.

Ends up there’s an interesting design problem at the root of the incident:

Actually, Patron X said he had no idea he was the culprit. He said
his company replaced his BlackBerry with an iPhone the day before
the concert. He said he made sure to turn it off before the
concert, not realizing that the alarm clock had accidentally been
set and would sound even if the phone was in silent mode.

Ouch! I certainly understand the design tradeoff: would you rather
put people at risk of public humiliation when their silent phones
makes noise, or would you rather have somebody sleep through an
important meeting because they silenced their phone, forgetting
about their alarm clock?

I’d vote for silencing everything when you mute the phone, but
pop a warning if you mute the phone with alarms pending. Or maybe
a warning that lets you choose whether you want to also silence
alarms or not?

I agree with Biancolo that this is a tricky trade-off, but I disagree with his suggestions. Adding alerts and confirmation prompts is seldom a good idea, and would not help at all when you toggle the mute switch without even looking at the iPhone. (I frequently toggle that switch without taking the phone out of my pocket.)

I think the current behavior of the iPhone mute switch is correct. You can’t design around every single edge case, and a new iPhone user who makes the reasonable but mistaken assumption that the mute switch silences everything, with an alarm set that he wasn’t aware of, and who is sitting in the front row of the New York Philharmonic when the accidental alarm goes off, is a pretty good example of an edge case.

Whereas if the mute switch silenced everything, there’d be thousands of people oversleeping every single day because they went to bed the night before unaware that the phone was still in silent mode.